首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1190415篇
  免费   77961篇
  国内免费   2695篇
耳鼻咽喉   14361篇
儿科学   41485篇
妇产科学   31845篇
基础医学   166396篇
口腔科学   29381篇
临床医学   103368篇
内科学   227547篇
皮肤病学   23740篇
神经病学   96551篇
特种医学   47943篇
外国民族医学   307篇
外科学   182431篇
综合类   26858篇
现状与发展   1篇
一般理论   387篇
预防医学   96761篇
眼科学   25426篇
药学   82487篇
  4篇
中国医学   2817篇
肿瘤学   70975篇
  2018年   33463篇
  2017年   26514篇
  2016年   30707篇
  2015年   11692篇
  2014年   15354篇
  2013年   22951篇
  2012年   36177篇
  2011年   52773篇
  2010年   37725篇
  2009年   29639篇
  2008年   50096篇
  2007年   55288篇
  2006年   31668篇
  2005年   32632篇
  2004年   33446篇
  2003年   33998篇
  2002年   30713篇
  2001年   47434篇
  2000年   48834篇
  1999年   40613篇
  1998年   11488篇
  1997年   10465篇
  1996年   10356篇
  1995年   9948篇
  1994年   9314篇
  1993年   8638篇
  1992年   32387篇
  1991年   31654篇
  1990年   31190篇
  1989年   30024篇
  1988年   27295篇
  1987年   27457篇
  1986年   25539篇
  1985年   24712篇
  1984年   18478篇
  1983年   15586篇
  1982年   9391篇
  1981年   8387篇
  1979年   16952篇
  1978年   12277篇
  1977年   10332篇
  1976年   9827篇
  1975年   10187篇
  1974年   12362篇
  1973年   11856篇
  1972年   10884篇
  1971年   10117篇
  1970年   9412篇
  1969年   8770篇
  1968年   8131篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Molnár  B.  Aroca  S.  Dobos  A.  Orbán  K.  Szabó  J.  Windisch  P.  Stähli  A.  Sculean  A. 《Clinical oral investigations》2022,26(12):7135-7142
Clinical Oral Investigations - To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with...  相似文献   
2.

Interstitial lung disease (ILD) represents a significant cause of morbidity and mortality in systemic sclerosis (SSc). The purpose of this study was to examine recirculating lymphocytes from SSc patients for potential biomarkers of interstitial lung disease (ILD). Peripheral blood mononuclear cells (PBMCs) were isolated from patients with SSc and healthy controls enrolled in the Vanderbilt University Myositis and Scleroderma Treatment Initiative Center cohort between 9/2017–6/2019. Clinical phenotyping was performed by chart abstraction. Immunophenotyping was performed using both mass cytometry and fluorescence cytometry combined with t-distributed stochastic neighbor embedding analysis and traditional biaxial gating. This study included 34 patients with SSc-ILD, 14 patients without SSc-ILD, and 25 healthy controls. CD21lo/neg cells are significantly increased in SSc-ILD but not in SSc without ILD (15.4 ± 13.3% vs. 5.8 ± 0.9%, p = 0.002) or healthy controls (5.0 ± 0.5%, p < 0.0001). While CD21lo/neg B cells can be identified from a single biaxial gate, tSNE analysis reveals that the biaxial gate is comprised of multiple distinct subsets, all of which are increased in SSc-ILD. CD21lo/neg cells in both healthy controls and SSc-ILD are predominantly tBET positive and do not have intracellular CD21. Immunohistochemistry staining demonstrated that CD21lo/neg B cells diffusely infiltrate the lung parenchyma of an SSc-ILD patient. Additional work is needed to validate this biomarker in larger cohorts and longitudinal studies and to understand the role of these cells in SSc-ILD.

  相似文献   
3.
4.
Coronavirus disease-19 (COVID-19) caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is now a pandemic threat. This virus is supposed to be spread by human to human transmission. Cellular angiotensin-converting enzyme 2 (ACE2) is the receptor of SARS-CoV-2 which is identical or similar in different species of animals such as pigs, ferrets, cats, orangutans, monkeys, and humans. Moreover, a recent study predicted that dogs might be secondary hosts during the evolution of SARS-CoV-2 from bat to human. Therefore, there is a possibility of spreading SARS-CoV-2 through domestic pets. There are now many reports of SARS-CoV-2 positive cases in dogs, cats, tigers, lion, and minks. Experimental data showed ferrets and cats are highly susceptible to SARS-CoV-2 as infected by virus inoculation and can transmit the virus directly or indirectly by droplets or airborne routes. Based on these natural infection reports and experimental data, whether the pets are responsible for SARS-CoV-2 spread to humans; needs to be deeply investigated. Humans showing clinical symptoms of respiratory infections have been undergoing for the COVID-19 diagnostic test but many infected people and few pets confirmed with SARS-CoV-2 remained asymptomatic. In this review, we summarize the natural cases of SARS-CoV-2 in animals with the latest researches conducted in this field. This review will be helpful to think insights of SARS-CoV-2 transmissions, spread, and demand for seroprevalence studies, especially in companion animals.  相似文献   
5.
6.
7.
8.
9.
Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study...  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号